Apparatus for heating synthetic substance threads

ABSTRACT

The heating element cells are constructed with double-tube sides to conduct the threads through the inner tubes while the heat carrier flows through the outer tubes. The heat carrier maintains the path of the threads within the double tube under a substantially uniform heat for substantially the entire passage.

United States Patent [72] Inventor Max Borner Stuttgart-Vaihingen,Germany [21] Appl. No. 792,090

[22] Filed Jan. 17,1969

[45] Patented Jan. 12, 1971 [73] Assignee Sulze: Brothers, Ltd.

Winterthur, Switzerland a corporation of Switzerland [32] Priority Jan.25, 1968 [3 3] Switzerland [54] APPARATUS FOR HEATING SYNTHETICSUBSTANCE THREADS 7 Claims, 3 Drawing Figs.

[52] U.S.Cl

[51] Int. Cl F27b 9/28 [50] Field ofSearch 263/3; 34/154; 57/34HS [56]References Cited UNITED STATES PATENTS 2,910,761 11/1959 Bley 1 57/34HS3,283,414 11/1966 Crouzet 34/154 Primary Examiner-John J. CambyAttorney-Kenyon & Kenyon, Reilly, Carr & Chapin ABSTRACT: The heatingelement cells are constructed with double-tube sides to conduct thethreads through the inner tubes while the heat carrier flows through theouter tubes. The heat carrier maintains the path of the threads withinthe double tube under a substantially uniform heat for substantially theentire passage.

PATENTEDJAMBISH 3.554.503

sum 3 BF 3 In genfor MAX BURNER Y 5 7%? A 7'TOF? 7 APPARATUS FOR HEATINGSYNTHETIC SUBSTANCE THREADS i This invention relates to an apparatus forheating synthetic substance threads; More'particularly, this inventionrelates to the use of aflowable heat carrier for heating syntheticthreads in false-twisting machines.

l-leretofore, in textile machines for curly yarn, such as falsetwistingmachines, heating devices have been used to heat synthetic threads to atemperature which permits twisting and setting of the thread duringpassage of the threads through the machines. Further, these heatingdevices have been constructed to maintain the thread at the temperatureat which the thread becomes plastic. Usually, these heating devicesthrough which the threads have run have been heated electrically.However, this often creates difficulties, particularly when the threadpasses through at a relatively high speed. For example, one difficultyarises because it is difficult to hold the thread, which passes throughrelatively rapidly, for the necessary time at the necessary temperature,about 200 (3., without making the heating device unallowably long in thedirection of the This This is due to the fact that starting from theplace or zone of maximum temperature, there-is a relatively steeptemperature gradient toward the thread inlet and thread outlet of theheating device.

Accordingly, it is an object of this invention, even in the case ofmachines with which the thread passes through the heating device at arelatively high speed, to achieve sufficiently high and uniform heatingof synthetic threads for a suf ticiently long period of time toefficiently twist the same.

It is another object of the invention to heat syntheticthreads to a hightemperature in a relatively'small space.

it is another object of the invention to heat synthetic threads throughthe use of a tlowable heat carrier.

It is another object of the invention to pass a thread through auniformly heated passage. I I

Briefly, the invention provides an apparatus which can be attached totextile machines, such as false -twisters, for heating synthetic threadsto predetermined temperatures. The apparatus utilizes a flowable heatcarrier and a system of tubing wherein the threads can be substantiallyunifonnly heated dur' ing passage therethrough. i

The apparatus includes I are constructed with two longitudinaldouble-tube sides through each of which a thread runs in the interiorspace and a heat carrier flows in concentric relation in the surroundingspace. In addition, each'cell has a pair of transverse sides whichconnect with the outer tubes of each of the double-tube sides andthroughaconnection containing a throttling means to a common distributoror common'collector, respectively, for supplying and removing the heatcarrier to and from the double-tube sides. The distributor andcollector, in turn, are

connected to a suitable heating means which serves to heat the heatcarrier to the required temperature;

In one embodiment, the transverse. sides of the cells are' made ashorizontal connecting tubular parts which extend beyond the ends of thedouble-tube sides and are closed at both ends, while the outer tubes ofthe double tubes. are welded to the inside surfaces of the connectingtubular parts and the inner tubes of the double tubes pass through theconnecting tubular parts and are welded to their outside surfaces. Theparticular advantage of this form of construction is that dead spaces inwhich impurities, air or water, may collect are avoided. This form ofconstruction moreover ensures that when the heating apparatus is flushedout, the impurities can easily escape, and that during the filling ofthe system with the heat carrier neither water nor air collects init.

It is. moreover advantageous to surround each heatingapparatus of aplurality of suchwhich are secured to a textile machine and which areeach composed of a plurality of cells,

- with its own insulation, and to fasten it in the textile machines I bymeans of its associated distributor or collector conduit.

heat all'the threads in a machine it is therefore advantageous for eachheating apparatus of this machine tobe combined framelike cell used in aheating apparatus according to the invention;

FIG.2 illustrates-a view taken on line lI-ll of' FIG. 1 of a heatingapparatus containing a plurality of framelike cells according to theinventionjand FIG. 3 schematically illustrates a construction of aplurality of heating apparatuses for a pair of textile machines with acirculation system for the heat carrier.

' Referring to FIGS. 1 and 2, the heating apparatus is constructed as aheating element 14 which includes a plurality of framelike cells 2, forexample, of rectangular shape, through each of which a pair of threads 1run in a downward vertical direction. Each cell 2 is formed by a pair ofvertically disposed double-tube sides formed by an inner tube 4 and alarger outer tube 4. The outer tube 5 surrounds the inner tube 4 with aslight clearance so that a heat carrier, for example, a synthetic highcirculate oil, can circulate therebetween. The selection of specificheat to be high, so that only a small quantity of oil a plurality oftramelike cells which deposited from the threads 1. The inset tubes 3are fitted into n A number of heating apparatuses are generally disposedin a textile machine, and each of them contains, for example, 8 to 10cells, heating some 16 to 20 threads! border to uniformly need be keptcirculating.

. in addition, because binding mediums become separated from the threads1 during heating and deposit in the cooler zones of the heatingapparatus, i.e. in the vicinity of the thread entryand thread exit, aninset tube-3, for example of aluminum, is fitted into each inner tube 4of a double-tube side in order to conveythe threads 1 and to pick hp anymaterials the inner tubes 4 in a manner so that at the time of heatingup and expansion, a good heat conducting connection is made connectingtubes 6, 7 which connect the upper and lower ends of the double-tubesides together. Each of the connecting I tubes 6, 7 extends horizontallybeyond the outer tubes 5 and are capped at each end by closure caps 8.Also, the outer tubes 5 are secured, as by welding, "to the inside ofthe connecting tubes 6, 7 with respect to the cell configuration whilethe inner tubes 4 extend through the connecting tubes 6, 7 and aresecured, as by welding, to the outside-of the connecting tubes 6, 7 asshown.

Each connecting tube 6, 7 communicates with a tubular element 1 l at thelowest and highest points, respectively, midway between the double-tubesides. The tubular element 11 of the lower connecting tube 6 furthercommunicates with a distributor conduit 12 while the tubular element ofthe upper connecting tube 7 communicates with a collector conduit 13. inthis -way, the flowable heat carrier medium can be supplied from thedistributor conduit 12 to the space between the tubes 4, 5 of thedouble-tube sides and removed via the collector conduit 13. Further, byconstructing the connecting tubes 6, 7 with exdead spaces are especiallyavoided in the system in which the heat carrying oil circulates, and inwhich, after the system is filled with the heat carrier, there mightcollect deposits of impurities, of water or air. Through thisarrangement, with which there exist no pockets and recesses for foreignsubstances which might otherwise disturb uniform circulation of the heatcarrier and a uniform transfer of heat from the heat carrier to thetubular elements, or which might produce steam hammering during thefilling of the system, the oil preferably rises from the bottom to thetop. Thus, the oil reaches all angles and corners and floats out anyforeign substances, since in going from a horizontal to a vertical partof the cell 2, and in going to the distributing and collecting conduitsl2 and 13, it is ensured that the transition places are always situatedat the highest or lowest point of the horizontal part.

The tubular elements 11, which are made as throttling tubes, or whichmay, however, also be made of wider tubes having throttling placestherein ensure a uniform distribution of the heat carrier among theindividual cells 2 of the, heating element 14 (FIG. 2), without specialregulatory elements being required to ensure this. The great resistanceto flow of the tubular elements 11 hereby ensures that at allbranch-offs to the individual cells 2 of a heating element 14 uniformityof pressure shall prevail in the distributor conduit 12 and in thecollector conduit 13.

As is evident from FIG. 2, the distributor conduit 12 andthe collectorconduit 13 extend over the entire length of the heating element, andconsist of horizontal tubes which are closedat one end by a closure cap8 and open at the other end into connection conduits 15 and 16 whichlead to the forward flow and backward flow system 18, 19 (FIG. 3) commonto the complete machine. The conduits 15 and 16, which are made asthrottling tubes forthe heating element 14, are each connectedeccentrically to the distributors and collectors 12 and 13,respectively, in order to avoid any dead space.

Referring to FIG. 2, the complete heating element 14 consists of aplurality of cells 2 connected in pairs to the same distributing andcollecting conduit respectively, and is surrounded by a common highgrade insulation 17, for example, a mineral wool. The collector conduit13 which is partly embedded in a layer of suitable insulation, can bymeans of holding devices (not shown) serve to fasten theindividualheating elements 14 in the textile machine. Also, guideelements (not shown) can then be provided on the distributor conduit 12to prevent the heating elements 14, suspended in the textile machine,from swinging pendulum fashion.

The diagram of FIG. 3 shows by one example how a plurality of heatingelements 14 belonging, for example, to two textile machines, can becombined into one group and can be connected to a main conduit system26, 27 in which a source of heat (not shown) is disposed.

As shown, each heating element group forms a closed circulation systemfor the heat carrying oil wherein the oil is circulated by a pump 20through the advance flow conduit 18, the individual heating elements 14,the return flow conduit 19, and a mixing tube 21 that is installed inthe advance flow conduit 18 through a branch line 23 having a checkvalve 22 disposed therein. The pump pressure in this system amounts,depending on the size of the system, for example to some to 8atmospheres gauge. The temperature of the inflow 18 is adjusted to adesired value by a temperature gauge 24 installed in the advance flowconduit 18, for example, to a temperature of 220 C., in such a way thata relatively small partial quantity is carried away from the machine scircuit through a regulatory valve 25 installed in the return flowconduit 19 and controlled by the temperature gauge 24 and is fed into areturn flow main conduit 26 which leads to a source of heat, a boilerfor example (not shown). At the same time, an equal partial quantity issupplied anew into the machines circuit from a feed conduit 27,connected to the advance flow conduit 18 at a temperature of some 280 to290 C., by way of a filter 28 and the mixing tube 21. The regulatoryvalve 25 in the return flow line 18 is further bridged over by a bypassline 30 provided with a manual control valve 29 so that the system, inthe event of some derangement or failure of its regulatory devices, canbe maintained manually at the desired temperature. Another bypass line32, having a, shut off valve on device 33, can short circuit the filter28, to make it possible to clean the filter 28 from time to time duringoperation.

The pump 20 can suitably be a commercially obtainable rotary pump withslipring sealing, be cause such pumps lose very little through leakage.For the temperature gauge 24, a bimetallic gauge may, for example, beused. Further, for purposes of regulation, it is advantageous to makeuse of electropneumatically controlled organs because they actrelatively quickly, i.e. without much lag.

The circulation system of the machines circuit is laid out in such a waythat the quantity of oil circulated in unit time through the pump 20,conduits 18, heating elements 14, conduits 19, branch line 23 and mixingtube 21 is approximately 20 times the quantity flowing into and out ofthe feed conduit 27 and return flow conduit 26. Moreover, the heatcarrying oil should not differ more than 2 C. in temperature at itsinflow into and outflow from the system.

As has already been mentioned, the selection of the heat carrier dependson the maximum temperature reached. Both the heating elements 14 andalso all the inflow and outflow tubes connected to them should be madeof suitable temperature withstanding tubes. For example, in the case oftubes for temperatures below 300 C., by tubes designated St. 35.29should be used, and for temperatures from 300 to 400 C., by tubes markedSt. 35.:8 should be used.

The construction of the heating element 14 of individual framelike cells2 with the double tubes 4, 5 through which the threads 1 run makes itpossible to manage with a relatively small quantity of filled-in .heatcarrier. Furthermore, the long path for the threadsl, situated betweenthe connecting tubes 6 and 7, ensures that the threads are kept atapproximately the same temperature for their entire length passingthrough the tubes 4, 5 which has not been obtained with the arrangementavailable up to the present time. Through the installation of thethrottling tubes 11 between the conduits 12 and 13, respectively,uniform pressure distribution is ensured in the distributing andcollecting conduits l2 and 13, which ensures the individual cells 2receiving equal quantities of heat, without being necessary to providespecial regulatory elements for this.

Iclaim:

1. An apparatus for heating synthetic threads comprising:

at least one heating element having a plurality of framelike cellstherein, each cell including a pair of vertical doubletube sides and apair of transverse tubes, each doubletube side having an inner tubedefining a passage for a thread and a concentric outer tube defining aconcentric passage for a heat carrier about said inner tube and beingconnected at opposite ends to a respective transverse tube;

a pair of throttling tube means connected respectively to each saidtransverse tube for throttling a flow of heat carrier therethrough, oneof said throttling tube means being connected tothe lowermost side ofthe lower transverse tube and the other throttling tube means beingconnected to the highermost side of the upper transverse tube;

a common distributor connected to each throttling tube means of saidlower transverse tubes for supplying the heat carrier uniformly to eachcell; and

a common collector connected to each throttling tube means of said uppertransverse tubes for removing the heat carrier from each cell.

2. An apparatus as set forth in claim 1 wherein said transverse tubesextend horizontally beyond each of said doubletube sides and whereineach said outer tube is secured to the inside of a respective transversetube and each said inner tube passes through said transverse tube and issecured to the outside of said transverse tube.

3. An apparatus as set forth in claim 1 which further comprisesinsulation about said heating element.

4. An apparatus as set forth in claim 1 which comprises a plurality ofsaid heating elements disposed in at least one group and a heat carriercirculation system connected to said heating elements of said group tocirculate the heat carrier uniformly through said heating elements.

5, An apparatus as set forth in claim 4 wherein said circulation systemincludes means for mixing the outflow of heat carrier from each saidcollector with the supply of heat carrier to each said distribution toregulate the temperature of the heat carrier supplied to each group ofheat elements.

6. An apparatus as set forth in claim I further comprising an inset tuberemovably fitted in each inner tube of said doubletube sides fordepositing of thread impurities therein.

7. An apparatus as set forth in claim 1 further comprising means forsupplying a heat carrier to said distributor including a conduiteccentrically connected axially to said distributor and means forremoving the heat carrier from said collector including a conduiteccentrically connected axially to said collector.

1. An apparatus for heating synthetic threads comprising: at least oneheating element having a plurality of framelike cells therein, each cellincluding a pair of vertical doubletube sides and a pair of transversetubes, each double-tube side having an inner tube defining a passage fora thread and a concentric outer tube defining a concentric passage for aheat carrier about said inner tube and being connected at opposite endsto a respective transverse tube; a pair of throttling tube meansconnected respectively to each said transverse tube for throttling aflow of heat carrier therethrough, one of said throttling tube meansbeing connected to the lowermost side of the lower transverse tube andthe other throttling tube means being connected to the highermost sideof the upper transverse tube; a common distributor connected to eachthrottling tube means of said lower transverse tubes for supplying theheat carrier uniformly to each cell; and a common collector connected toeach throttling tube means of said upper transverse tubes for removingthe heat carrier from each cell.
 2. An apparatus as set forth in claim 1wherein said transverse tubes extend horizontally beyond each of saiddouble-tube sides and wherein each said outer tube is secured to theinside of a respective transverse tube and each said inner tube passesthrough said transverse tube and is secured to the outside of saidtransverse tube.
 3. An apparatus as set forth in claim 1 which furthercomprises insulation about said heating element.
 4. An apparatus as setforth in claim 1 which comprises a plurality of said heating elementsdisposed in at least one group and a heat carrier circulation systemconnected to said heating elements of said group to circulate the heatcarrier uniformly through said heating elements.
 5. An apparatus as setforth in claim 4 wherein said circulation system includes means formixing the outflow of heat carrier from each said collector with thesupply of heat carrier to each said distribution to regulate thetemperature of the heat carrier supplied to each group of heat elements.6. An apparatus as set forth in claim 1 further comprising an inset tuberemovably fitted in each inner tube of said double-tube sides fordepositing of thread impurities therein.
 7. An apparatus as set forth inclaim 1 further comprising means for supplying a heat carrier to saiddistributor including a conduit eccentrically connected axially to saiddistributor and means for removing the heat carrier from said collectorincluding a conduit eccentrically connected axially to said collector.